Drop miscellanea/secure_boot_mode_{gadget} for platforms that don't support it

[amalinowski75]

Enhancement Proposal

Pn RPis there is no secure boot but it is still tested.

Error message is: ERROR: Unexpected bootloader name piboot

Example test run: http://10.102.156.15:8080/job/cert-cm4l-arm64-pi-kernel-24-beta/7/testReport/com.canonical/certification__miscellanea_secure_boot_mode_pi/com_canonical_certification__miscellanea_secure_boot_mode_pi/

[syncronize-issues-to-jira[bot]]

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The internal ticket has been created: https://warthogs.atlassian.net/browse/CHECKBOX-1571.

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[omar-selo]

For reference here are other non RPI machines that don't have secure boot:

aaeon-lookout-canyon-ehl
aaeon-lookout-canyon-tgl
dawson-j-uc24